//Connect all completely unconnected points to a connected point, making sure all cells are reachable.
void ConnectUnconnectedPoints(LevelBlockRequirements[,] basicGrid)
{
int hBlocks = Width / BlockWidth, vBlocks = Height / BlockHeight;
//Store which blocks weren't connected.
bool[,] isConnected = new bool[hBlocks, vBlocks];
List<Point> unconnectedPoints = new List<Point>();
for (int i = 0; i < hBlocks; i++)
{
for (int j = 0; j < vBlocks; j++)
{
isConnected[i, j] = ! basicGrid[i, j].IsOnlyWalls();
if (! isConnected[i, j])
unconnectedPoints.Add(new Point(i, j));
}
}
bool connectedAnythingThisRound;
while (unconnectedPoints.Count > 0)
{
connectedAnythingThisRound = false;
List<Point> removedUnconnectedPoints = new List<Point>(); //A list to store points we remove as changing a list during foreach is impossible
unconnectedPoints.Shuffle(); //Shuffle the points so that they connect in a more random way.
foreach (Point point in unconnectedPoints)
{
int i = point.X, j = point.Y; //Temporary store the x and y of this point.
List<Point> possiblePoints = new List<Point>(); //Points to connect to.
if (i > 0 && isConnected[i - 1, j])
possiblePoints.Add(new Point(i - 1, j));
if (i < hBlocks - 1 && isConnected[i + 1, j])
possiblePoints.Add(new Point(i + 1, j));
if (j > 0 && isConnected[i, j - 1])
possiblePoints.Add(new Point(i, j - 1));
if (j < vBlocks - 1 && isConnected[i, j + 1])
possiblePoints.Add(new Point(i, j + 1));
if (possiblePoints.Count != 0)
{
//Connect this point to a random other one.
ConnectPoints(basicGrid, new List<Point>() { point, possiblePoints.GetRandomItem() });
isConnected[i, j] = true; //Mark this point as connected.
connectedAnythingThisRound = true;
removedUnconnectedPoints.Add(point);
}
}
foreach (Point point in removedUnconnectedPoints)
unconnectedPoints.Remove(point);
//Give up if we couldn't connect anything at all.
if (! connectedAnythingThisRound)
break;
}
}
//Connect any number of points on the level grid.
void ConnectPoints(LevelBlockRequirements[,] basicGrid, List<Point> points)
{
if (points.Count == 0)
return;
//Choose a random point and connect that to each other point.
//This automatically guarantees that each point is connected to each other point, as
//you can always travel to the first point and then to the target point.
Point point = points.GetRandomItem();
for (int i = 0; i < points.Count; i++)
{
Point otherPoint = points[i];
if (point == otherPoint)
continue;
//Check how far we have to travel
Point distanceDifference = new Point(otherPoint.X - point.X, otherPoint.Y - point.Y);
//And store the directions we have to take into a RandomCollection of directions
RandomCollection<Direction> directionsToTravel = new RandomCollection<Direction>();
if (distanceDifference.X < 0)
directionsToTravel.Add(Direction.Left, -distanceDifference.X);
if (distanceDifference.X > 0)
directionsToTravel.Add(Direction.Right, distanceDifference.X);
if (distanceDifference.Y < 0)
directionsToTravel.Add(Direction.Up, -distanceDifference.Y);
if (distanceDifference.Y > 0)
directionsToTravel.Add(Direction.Down, distanceDifference.Y);
//Then actually travel from the first point to the second one.
Point position = point;
while (directionsToTravel.Count != 0)
{
switch (directionsToTravel.Take())
{
case Direction.Left:
basicGrid[position.X, position.Y].LeftSideType = SideType.Exit;
position.X -= 1;
basicGrid[position.X, position.Y].RightSideType = SideType.Exit;
break;
case Direction.Right:
basicGrid[position.X, position.Y].RightSideType = SideType.Exit;
position.X += 1;
basicGrid[position.X, position.Y].LeftSideType = SideType.Exit;
break;
case Direction.Up:
basicGrid[position.X, position.Y].TopSideType = SideType.Exit;
position.Y -= 1;
basicGrid[position.X, position.Y].BottomSideType = SideType.Exit;
break;
case Direction.Down:
basicGrid[position.X, position.Y].BottomSideType = SideType.Exit;
position.Y += 1;
basicGrid[position.X, position.Y].TopSideType = SideType.Exit;
break;
}
}
}
}
